Industrial hemp and other forms of cannabis contain a variety of different cannabinoids, which predominantly each contain a carboxyl group. These cannabinoid carboxylic acids bind the human cannabinoid receptors with relatively low affinity. The production of therapeutic pharmaceuticals and psychoactive drugs from cannabis therefore generally utilizes a decarboxylation step, which typically involves prolonged heating. This heating also generally introduces other chemical modifications that are typically undesirable.
Marijuana produces tetrahydrocannabinolic acid (“THCA”), for example, which lacks robust pharmacological effects. THCA is converted into the psychoactive molecule tetrahydrocannabinol (“THC”) by decarboxylation, which occurs when marijuana is smoked. THC is commercially produced from THCA by heating the THCA for several hours. Prolonged heating nevertheless results in undesirable side products. THCA can be oxidized, for example, into cannabinolic acid (“CBNA”), which decomposes into cannabinol (“CBN”). CBNA lacks well-known pharmacological properties, and CBN causes drowsiness.
Industrial hemp similarly produces cannabidiolic acid (“CBDA”), which lacks robust pharmacological effects. CBDA is converted into the pharmaceutical cannabidiol (“CBD”) by decarboxylation. CBD is commercially produced from CBDA by heating the CBDA for several hours. Prolonged heating nevertheless results in undesirable side products including CBN.
The industrial production of decarboxylated cannabinoids also degrades and vaporizes other molecules found in cannabis including terpenes, terpene alcohols, terpenoids, and flavonoids, which often impart favorable characteristics to products containing cannabinoids including favorable flavor and aroma.
Improved methods to decarboxylate cannabinoids are desirable.